

The button becomes grey and you have disabled it successfully. They recently added an advertising system to the videos that overlays an ad over the first 10 seconds of the vid, a script that the Wiis Opera isnt able to use yet.

Follow the steps to disable an add-on on Firefox: Click Open menu > Add-ons > Extensions, click the blue button next to an extension. If you want to play YouTube videos under the Firefox normal mode or the method doesn’t come into it, try the following methods. Languages/zh_TW, languages/de_DE, languages/da_DK, languages/ru_RU, languages/sl_SI, languages/ar, languages/es_PE, languages/sv_SE, languages/pt_PT, languages/tr_TR, languages/it_IT, languages/fi_FI, languages/cs_CZ, languages/sk_SK, languages/el_GR, languages/vi_VN, languages/es_AR, languages/zh_CN, languages/es_MX, languages/he_IL, languages/ja_JP, languages/nb_NO, languages/es_ES, languages/nl_NL, languages/fr_FR, languages/fa_IR, languages/ro_RO, themes/EnvisionSchoolsMainīcmath, bz2, calendar, cgi-fcgi, Core, ctype, curl, date, dba, dom, enchant, ereg, exif, fileinfo, filter, ftp, gd, gettext, gmp, hash, iconv, imagick, imap, intl, json, ldap, libxml, mbstring, mcrypt, mhash, mysql, mysqli, odbc, openssl, pcntl, pcre, PDO, pdo_dblib, pdo_mysql, PDO_ODBC, pdo_pgsql, pdo_sqlite, pgsql, Phar, posix, pspell, readline, recode, Reflection, session, shmop, SimpleXML, soap, sockets, SPL, sqlite3, standard, sysvmsg, sysvsem, sysvshm, tidy, tokenizer, wddx, xml, xmlreader, xmlrpc, xmlwriter, xsl, Zend Guard Loader, zip, zlib. Repeat the procedure until you find the one causing the YouTube not working on Firefox issue.
